Hot flashes and other climacteric symptoms affect 75% of postmenopausal women in the US and are associated with higher rates of depression and sleep disturbance. Although hormone replacement therapy (HRT) is highly effective in reducing hot flashes, there is concern that HRT is associated with an increased risk of thrombo-embolic events, breast cancer and ovarian cancer. In addition, it is poorly tolerated in clinical practice, with about 30% of women discontinuing therapy after a mean of 4.5 months. Many other women have a contraindication to HRT, such as a history of an estrogen-sensitive tumor, liver dysfunction, or a hypercoagulable state. Safe, effective, and well-tolerated alternative therapies for hot flashes are needed. Gabapentin is a gamma-aminobutyric acid (GABA)-analog approved in 1994 for the treatment of seizures. Since then, it has been shown that gabapentin is efficacious for numerous off-label indications such as neuropathic pain, anxiety, bipolar disorder, and migraine headaches. The investigators have reported that gabapentin is associated with a reduction in the frequency of hot flashes in an uncontrolled series of postmenopausal women who were taking gabapentin for other indications. The investigators also report here preliminary data from a randomized, placebo-controlled trial showing that low-dose gabapentin was associated with a greater reduction in hot flash frequency than placebo after 12 weeks of treatment. However, it is not known whether the efficacy of gabapentin in the treatment of hot flashes and other menopausal symptoms is comparable to that of estrogen, the gold standard. A randomized trial of gabapentin, estrogen and placebo is needed to inform clinicians as to whether gabapentin is an effective alternative to estrogen. The first major aim of this proposal is to assess the screening and recruitment of menopausal women into a randomized trial of gabapentin, estrogen and placebo in the treatment of climacteric symptoms. The second major aim is to obtain preliminary estimates of the frequency and severity of climacteric symptoms among women receiving gabapentin, estrogen and placebo. Pilot data from these two aims will permit estimates of sample-size requirements for a full-scale randomized trial, and of the overall feasibility and cost of such a trial.